Rajarshi wrote: > This is a slightly naive question, but I know that 0 can be used to > represent False. So > >>>> 0 == False > True > > But, I know I can use [] to represent False as in > >>>> if not []: print 'empty' > ... > empty > > But then doing the following gives a surprising (to me!) result > >>>> [] == False > False > > Could anybody point out why this is the case?
"if foo:" does not check if "foo == True" or "foo == False" but rather "bool(foo)". For empty lists, strings, tuples, dicts and some other things, "bool(foo) == False", while for lists, etc., with at least one element, "bool(foo) == True". -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco -- http://mail.python.org/mailman/listinfo/python-list
